A relationship is a lot like a roller coaster — there are the intense highs of infatuation but also the lows. Cosmo tells you how to endure — and even enjoy — the ups and downs of couplehood.

Most Read

It's easy to assume that a relationship is meant to be a straight line. You start at Point A (falling in love) and giddily sprint toward Point B (blissful coupledom), then finally to Point C (happily ever after). But in reality, every love journey is interrupted every so often when — bam! — you hit a rut. Maybe your lust takes a header, or perhaps you start spotting his flaws. Whatever the gripe with your guy and whenever it happens, this shift can make you feel like your relationship has ground to a halt...and cause you to wonder if you've hooked up with a guy who's all wrong for you. But before you ditch your previously perfect man, stop and consider this: Relationships are cyclical, and facing downtime isn't only inevitable, it's necessary. "When it comes to real love, ups and downs aren't aberrant, they're normal," says Pepper Schwartz, PhD, author of Everything You Know About Love and Sex Is Wrong. "It's only by moving through these highs and lows of a relationship that you can reach the deepest level of connection and forge a lasting relationship." Here are the phases you can expect to endure and tips on how to come through them as an even more solid couple than before.

Phase One
When you first link up with a new love, it's as if you've been transported to a different world: Planet Utopia, where every joke of his is hysterical, every meal you share is scrumptious, and every moment together is miraculous. You don't sleep much, you can't think straight, and if lust were a commodity, you could out-trump Trump. This period of infatuation might feel mysterious and mythic, but in fact, it has a strictly scientific explanation: hormones, hormones, hormones.

"When you meet someone you really like, you become infatuated, and your body produces a euphoria-inducing, adrenaline-like hormone," explains Pat Love, author of The Truth About Love. Call it the love buzz: You're so high on him during the first three to six months of the relationship that you're in awe of even his most inconsequential quirks, according to Helen Fisher, PhD, anthropologist and author of The First Sex. (The way he stirs his coffee gives you goose bumps — sound familiar?) In a recent survey of women in the early dating stage, Fisher found that 84 percent remembered trivial things their guy said or did, and 90 percent of those women daydreamed about the mundane moments.

Maximum momentum move: Live it up! Whether it's by putting him on a pedestal, having 48-hour sexathons or neglecting your friends and job a bit (and not feeling bad about it), this is your chance to enjoy the excitement and revel in each other. "When Dan and I started dating, we didn't get much sleep," says Amy,* 25. "But instead of wrecking our sex or intense conversations by worrying about being exhausted at work the next day, we made a pact to suck it up. It was so worth it." And although this blissfully intense period must end eventually, you can help to extend it. "Simply recalling the first time you saw him will give you a surge of that initial emotion," says Love. Or keep up your appreciation of his most swoon-worthy qualities by occasionally imagining him being sized up by another woman — what would she find most attractive about him? "People tend to lose sight of their partners' best sides, but looking at him from a stranger's perspective will remind you of what you find amazing about him," explains Paul Coleman, PsyD, author of 25 Stupid Mistakes Couples Make.

*Names have been changed.

Phase Two
While infatuation-extension tricks can buy you some extra sleep-optional nights and dreamy days, a love lull is inevitable, usually after three to six months of couplehood. The explanation is mostly physiological: Your overtaxed, overhyped brain can't sustain its amped-up state once its nerve endings become habituated to the infatuation hormone, explains Love. The symptoms of boy burnout: You're not writing his name in pancake syrup any more, you realize he has an annoying habit (actually several) — or you find yourself suddenly craving sleep instead of all-night sex.

Maximum momentum move: Don't freak out...or break up! After the intensity of stage one, it's natural to come off your high and wonder if he's the one for you. But rather than second-guessing your guy, realize that this phase is an unavoidable (and likely temporary) stretch on the way to a long-term relationship. So when your lust levels start to dip back toward normal, try not to focus on the letdown but see it as a new opportunity to find out how you click out of the sack, says Coleman. "After months of falling into bed as soon as we saw each other, Tom and I started to lose the urgency," says Amanda, 24. "I was still attracted to him, but sex wasn't the first thing on my mind whenever I saw him. At first it freaked me out, but then I realized that because we weren't obsessed with doing it, we had time to discover that we both love blues music, we both hate television sitcoms and a million other little things we never knew we had in common." So look at the sex slowdown as an opportunity to move your relationship forward. "Once the focus is off lovemaking, you can start to create real intimacy," explains Coleman. "Finding out how he acts in a variety of contexts is the best way to get to know your partner." So move beyond your strictly deux dates and introduce him to your friends, go out for drinks with his, and meet each others' families. Or see how he fares in your office, as Sandra, 25, did. "Dave and I had been together for five months, and after the initial intensity wore off, I started to wonder if we just weren't meant to be," she recalls. "Then he suggested meeting for lunch during the week. He met everyone in my office, and I saw a totally new side of him — I had no idea he would be so confident and charming." And if his quirks still get under your skin after you've seen his other sides, look at yourself before criticizing him. "When outside factors like your job or anything else that stresses you out creep back to the forefront of your life, it can reduce your tolerance of him," explains Coleman. And fixing those stressors may be enough for you to be able to cut him some slack...and even learn to love his faults.

Phase Three
Between six months and a year into the relationship, according to Love, you'll likely find that what once felt like a lull now feels like a comfort zone. Gradually, you go from being bummed that he's not perfect to feeling good because you're not either and he doesn't love you one bit less. From letting him see you in your pj's to enjoying a Blockbuster night, what used to seem dull now feels divinely cozy.

Maximum momentum move: Once you feel comfortable with each other and confident in the relationship, you should turn back to things that were a priority pre-him. And although establishing a life/boy balance is essential for an extended relationship, putting him on a back burner will spell disaster. "You may become so at ease that you think the relationship will thrive even if you don't spend as much time together or express your appreciation of each other," says Beatty Cohan, coauthor of For Better, for Worse, Forever. "In fact, not taking this opportunity to really enjoy being yourselves together can doom your relationship." So take pleasure in comforting him when he's sick and not stifling the snort in your laugh. Spend the occasional rainy Saturday night in your apartment in sweatpants together. When he comes home from work ragging on his boss, not only can you be there to feel his pain, but by now, you also know exactly where to kiss him to make it feel better. "Sometimes, when I'm exhausted from work, I'll go over to George's place, have two glasses of wine and crash," says Eileen, 30. "He loves that he's the one I want to be with when I'm so spent and that I feel so comfortable with him."

Phase Four
You've established a level of ease and friendship that will endure for the rest of your relationship, but you're not home-free. Although compatibility is key to a satisfying union, Love explains, you can get too complacent with each other and wonder if you've lost your spark forever.

Maximum momentum move: At this stage, boredom happens because you and your man have created a comfort cocoon. It's likely that you've let friends drop out of the picture or you've begun to blow off your individual hobbies to spend time together. But by isolating yourselves, you lose an important source of energy for the relationship. "It may not be that your relationship is boring — you may have become boring," says Coleman. Luckily, your apathy can be fixed by addressing issues outside the relationship, explains Schwartz. Rather than putting pressure on your guy to crank up the thrill-o-meter, try seeking out kicks on your own and encourage him to do the same. "After a year and a half of dating, I knew Pete and I were solid, but we were starting to feel like an old married couple," says Carmen, 21. "So instead of trying to pretend that we were on a first date, we made a pact to go our own way sometimes. He started playing in a recreational soccer league again; I started reporting as a stringer for the local newspaper. Instead of being bummed that we wouldn't see each other as much, when we finally did crawl into bed together, we were so glad to be there...and we had so much more to talk about."

Phase Five
Once you hit two years and beyond, chances are, you'll both feel intimately and intricately connected, says Love. Having stuck together through the spates of boredom and other periodic lows, you know from experience that what goes down must come up. So now, more than ever, you're confident that even a big blowout doesn't mean a breakup.

Maximum momentum move: Although you can revel in the high that comes from a committed relationship, coasting can kill your hard-won connection. "Taking each other for granted is still a risk," says Schwartz. To avoid letting your love fall apart due to neglect, make sure you always have an aim in sight. "When you're not working toward a common goal, it's easy to lose the incentive to stay in the relationship," explains Coleman. The most obvious objective is marriage, but you can also talk about raising a pet or saving for an exotic vacation. "When Rich and I first met, we talked about how we both wanted to live and work abroad one day," says Ellie, 27. "A few years later, we decided to try to make it a reality together — we both spoke to our bosses, looked into subletting our apartment, and researched what countries we'd most like to live in. Having a future plan that we were both so excited about not only brought us together, it was a way to make it clear to each other that we were in it for the long haul." Keep in mind that even the most connected couples repeat the less-appealing phases of the relationship cycle all over again. The good news? Each time you move through the highs and lows of coupledom, Love explains, you reach a deeper level of love. "The ups and downs create an intimacy that energizes you and takes you beyond even the apex of your first falling-in-love buzz."

How to know when your low point is not just a lull

You Don't Share Details
"If you've lost interest in what's happening in your time apart from each other, your connection will unravel, if it hasn't already," says Pepper Schwartz, PhD, author of Everything You Know About Love and Sex Is Wrong.

You're Resigned to Your Sex Rut
"If lovemaking is lackluster or on an extended hiatus and you don't care about fixing it, you may need to call it quits," says Beatty Cohan, coauthor of For Better, for Worse, Forever.

You Don't Bother Fighting
"If you can't communicate or solve problems effectively, you can't face the rigors of a long-term relationship," says Cohan.